Attention
IronPLC can only run very simple programs. The steps described are accurate but many language features are not yet supported.
RS¶
Reset-dominant bistable function block. A flip-flop where the reset input takes
priority: if both S and R1 are TRUE, the output Q1 is
FALSE.
IEC 61131-3 |
Section 2.5.2.3.1 |
Support |
Supported |
Inputs¶
Name |
Type |
Description |
|---|---|---|
|
|
Set input |
|
|
Reset input (dominant) |
Outputs¶
Name |
Type |
Description |
|---|---|---|
|
|
Output state |
Behavior¶
The output is computed as Q1 := NOT R1 AND (S OR Q1). When R1 is
TRUE, the output is cleared regardless of S. When only S is
TRUE, the output is set. The output retains its value between scans
(latching).
Example¶
This example shows that reset dominates: both S and R1 are TRUE,
yet output is FALSE.
See Also¶
SR — set-dominant bistable